Kirsi M. Järvinen


Curr Opin Allergy Clin Immunol. 2011;11(3):255-261. 

In This Article

How to Make a Diagnosis of Food-induced Anaphylaxis?

Making a clinical diagnosis of food-induced anaphylaxis can be challenging if there is no known history of food allergy or cutaneous involvement is lacking.[37] Furthermore, the fact that many foods are usually consumed at the same time may obscure identification of the triggering allergen. The diagnosis can also be difficult to make because of transience of symptoms due to endogenous production of catecholamines or prehospital administration of medications.

Currently, total tryptase level is the most commonly measured marker to establish a diagnosis of anaphylaxis. Tryptase levels increase immediately, peak at 1–2 h and return to baseline 24 h after complete resolution of symptoms. Levels are ideally obtained within 3 h of onset of symptoms and serial measurements may help establish a diagnosis of anaphylaxis.[62] Lack of tryptase elevation is commonly seen in food-induced anaphylaxis,[60,63] which may be due to slow onset of reactions or because mucosal mast cells and basophils, the major players in food-induced anaphylaxis, contain less to no tryptase as compared with skin mast cells.[25] Another laboratory marker of anaphylaxis is serum histamine which peaks at 10 min and disappears in 60 min and is therefore not a practical marker. Urinary histamine metabolites remain elevated for up to 24 h and may be helpful in establishing the diagnosis. Among other mast cell mediators, chymase, and mast cell carboxypeptidase A3 may be other potential markers of anaphylaxis.[64]

Oral food challenges are the gold standard for the diagnosis of food allergy but may elicit severe anaphylactic reactions including those requiring treatment with multiple doses of epinephrine.[24•,65] Therefore, presumptive diagnoses are more often made based on a convincing clinical history of anaphylaxis within 2 h of ingestion of a particular food allergen and detection of food allergen-specific IgE. Unfortunately, these tests are not always sensitive or highly specific.[25]


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